Radio circuit



May25, 1937. H. MARslsKE l 2,081,205

- RADIO CIRCUIT Filed June 9,1954

n INVENTOR Afd/2S Marys/e.

ATTOR EY Patented May 25, 1937 U N I T ED STATES .PATENT orI-iCf-E- Application '.Iunei- 9, 1934,. Seriali No.; 729,842 In Germany June'.19,.,.1933

'6 Claims.

My` invention relatestof'radiocircuits. of lthe vtypeemployed in the -art of Aradio i communicay'tion,.andmore specifically to a Vcircuit capable of :dualf operation, or in other-words,`capable of lhandling'two signals simultaneouslyv without interference Abetween them.

It is an object of my invention toprovide a system capable of functioning inthe reception and transmission ofsmore thanone signalzat the l same time, without the one -signalrbeing interferred with .by the other signal- It is another. objectief-'my invention to. provide 'a circuit'for reception of a plurality 'of signals or vprograms simultaneously, and capable of 'reo producing' .ther same on different'indicatingnin- -strum'ents An -additional object of my invention .is to Vprovide a radio circuit involving electrondischarge idevices, wherein the discharge idevices Aperform' double duty.

4A still further object 1of my invention'fis'to provide a radio systemzinvolving "electron vdischarge "devices Vwherein* the discharge devices function both as, radio frequency "and1 audio i frequency ampliers simultaneously.

.A Ystill further object Vof my invention "is to providea `radio circuit involving electron-discharge devices wherein the electron :discharge devices are capable. of amplifyingmoreA thanl one 30 .v program or, signal :simultaneously -Additional objects :of :myin-vention will kbe brought to :lightin the following description vof f the same.

As .an 'aid'to an understanding of vmy invention, reference willbe madeV to the accompanying drawing wherein I l.have .disclosed oneembodimentof-my invention in its simplest form.

Brcadly speaking, my invention embodies a radio circuit wherein a plurality of signals or 40 programs may be received simultaneously without interference from each other, the discharge devices and circuits being so arranged that one of the signals will pass through the tubes in one sequence, whereas the other signal will pass through the tubes in another sequence. Perhaps a better understanding of the invention may be had by reference to the accompanying drawing and by tracing the path of one signal through one sequential arrangement of the discharge de vices.

Referring to the drawing, therefore, for further explanation, I have disclosed my invention as embodied in a receiving circuit capable of receiving two programs simultaneously. The

signal in the form of a modulated carrier wave (Cl. Z50-9) across .1 theprimary .of transformeri43, whereby the signal: potential .developed across the resistor 5.1m the'antenna circuit will be impressed upon the -gri'd 'electrode Il. The amplified image of ther'signal potential `Will appear in the plate cir- -cuit `of :the discharge ydevice .9,.and will 'passi through acondenser I3 connected'n series v'With a crystal ydetector I5, whereby it' will' -be'detectedfv'and-broken up into its audiofrequency and radio frequencyfcomponents, the audio frequency component passing through the primary IlV ofaanfaudio transformer I9 through aplate Y Asupply :batterylZl to ground. The radio 'frequency eomponentis` by-passed around the translforme'r. primary |11 by :means of al by-pass condenser. 23 shunting the :primary winding. *Plate potential forthe discharge device is derived from .the battery-12| byway ofA the'resistor 25and a .loud speakerLZ'l or other-indicating device con- :nected in series therewith, the loud speaker act- "ing asa radioA frequency choke in the circuit.

The audio "frequency signalvariations developed across"r the .primary 1 I1 of the audio fre- .quency transformer l9aw'i1l induce'corresponding variations in :the secondary lwinding 129, which secondary' winding constitutes `the f audio `'frefzquency vinput. tothe -other electron discharge dev-ice'f3l shown,v `thuszim-pressing upon the-grid 33 of this second discharge device, signal potentials which are to be amplified by the second discharge device acting as an audio frequency amplifier. The signals will, therefore, appear in amplied form inthe audio frequency output of the device 3| which comprises a circuit including the series connection of the loud speaker 35, the resistor 31 and the plate supply battery 2| to ground. Passage of the audio signal energy through the detector circuit 4I etc. is prevented by the condenser 36 which imposes a high impedance to the iiow of energy at the audio frequencies. y

Thus, the signals corresponding to the modulations in the signal modulated carrier wave received upon the antenna circuit and impressed upon the input circuit of the rst electron discharge device 9 acting as a radio frequency ampliier, are reproduced in the output circuit of the second electron discharge device 3| acting as an audio frequency amplifier.

Now it will be noted that if the received signal were impressed upon the resistor 39 in the input circuit of the second electron discharge device 3|, a similar path may be traced in reverse sequence for the passage of the signal, this path including the condenser 36, crystal detector 4|, transformer 43, loudspeaker 21, and resistor 25. The signal will therefore be reproduced on the first loudspeaker 2`| or other indicating device,

rather than on the second one 35, as before. The

device 3| which functioned in the first instance as an audio frequency amplifier willvnow function as a radio frequency amplifier and the discharge device 9 which previously functioned as'a radio frequency amplifier will now function as the audio frequency amplifier. Y

By tuning the antenna circuits by means of condensers 3 and 45, the operator can discriminate between the directions in which the signal isto flow. Thus by tuning one antenna circuit vto one frequency, a program at that frequency will be impressed upon the input circuit of the electron discharge device whose grid is connected to thatantenna circuit, and the signal will travel or follow one predetermined sequence. Then should the other antenna circuit be tuned to a still different frequency a program on that frequency will be impressed upon the grid ofthe other discharge device and its signal will follow a different sequence of travel. rI'herefore, two programs may be received simultaneously, and when so received, each of the -tubes will function Vas a radio frequency amplifier for one program and an. audio frequency amplifier for the other program.

It will be apparent from the above description that my invention is capable of fulfilling the objects provided. While I have disclosed ,the same in its simplest form, and as applied to a radio receiver, the invention is susceptible to many applications and modifications without departing from the spirit of the invention. Its use is notlimited to a receiving circuit as it is conceivable that the invention may be` embodied in a transmitter for the simultaneous transmission of two signals each on a different carrier frequency.

Further, it should be apparent that in'lieu of the crystal detectors, detectors ofthe tube type may be employed, and my invention is not limited to any specific number of electron discharge devices, but may embody a plurality of amplifiers both for audio and radio frequencyamplification.

It may be pointed out further that various types of circuits well known in the art may be utilized in lieu of the specific circuits disclosed rby me.

I, therefore, do not desire to be limited to the specific details disclosed and described except as may be necessitated by the prior art and by the spirit of the appended claims.

I claim as my invention:

1. A radio circuit comprising a plurality of electron discharge devices, means for conveying a signal through said devices in one sequence wherein one of said discharge devices constitutes a radio frequency amplifier whereas another of said devices constitutes an audio frequency ampli- ,.fer, and means for simultaneously conveying another signal through said devices in a reverse sequence wherein said radio frequency amplifier .amplifies signals at audio frequencies and said audio frequency amplifier amplifies signals at l radio frequencies:

2;-In combination, a plurality of electron discharge `devices, a receiving circuit interconnecting said devices to constitute one a radio frequency amplifier and one an audio frequency amplifier, and another lcircuit electrically symmetrical to said rst circuit, said last circuit interconnecting said devices -to constitute said radio frequency amplifier an audio frequencyamplifier, and said audio frequency amplifier a radio frequency amplifier.

3. Aradio circuit comprising a plurality of electron discharge devices, an antenna 'connected to the input circuit of one of said discharge devices,

another antenna connected to the input circuit of another of said discharge devices, means for conveying a signal from one of said antennae through said devices in one sequence'and means for conveying another signal from the other of said form a different function in sequence and means enabling a different order of said devices to simultaneously perform a similar sequence of functions. 6. In. combination, a plurality of electron discharge devices, a circuit interconnecting said devices to constitute one a radio frequency amplil fier and one an audio frequency amplifier, and

another circuit electrically symmetrical to said first circuit, said last circuit interconnecting said devices to constitutesaid radio frequency amplier an audio frequency amplifier, and said audio frequency amplifier a radio frequency amplifier.

, HANS MARSISKE. 

